Misfire on cylinder #3, not sure of the cause (no spark, blown gasket, injector problem).
PO303 indicates a misfire on cylinder #3. Normally caused by bad spark plug or plug wire.
Trouble code P0303 means:Cylinder 3 misfire detected
PO303 , misfire engine cylinder # 3
po300-Random/multiple cylinder misfire detected. po303-Cylinder no. 3 misfire detected. po306-cylinder no. 6 misfire detected po300-Random/multiple cylinder misfire detected. po303-Cylinder no. 3 misfire detected. po306-cylinder no. 6 misfire detected
Trouble code P1131 means: Lack Of HO2S11 Switches - Sensor Indicates Lean
Trouble code P1131 means: Lack Of HO2S11 Switches - Sensor Indicates Lean
Trouble code P1131 means: Lack Of HO2S11 Switches - Sensor Indicates Lean
When a furnace's blinking code indicates an error, it means that there is a problem with the furnace that needs to be addressed. The blinking code is a way for the furnace to communicate what specific issue it is experiencing, and it can help a technician diagnose and fix the problem.
po303 is cylinder 3 misfire. I would start with cylinder #3 spark plug wire, look very carefully for chafed, worn or cracked spark plug wire, then check spark plug itself. If it is still acting up do a compression check on cylinder #3 to see if head gasket leaking. If all that looks okay it may be the #3 fuel injector failure.
How fix code P1140
how fix Code P1140 fuel air
Here is a video on how to fix engine code p0449